The Excel F.INV.RT function calculates the inverse of the (right-tailed) F Probability Distribution for a specified probability. If p = F.DIST.RT(x,…), then F.INV.RT(p,…) = x. The F distribution can be used in an F-test that compares the degree of variability in two data sets. For example, you can analyze income distributions in the United States and Canada to determine whether the two countries have a similar degree of income diversity.
The F.INV.RT function syntax has the following arguments:
- Probability (required argument) – This is the probability at which we evaluate the inverse Cumulative F Distribution. The value is between 0 and 1.
- Deg_freedom1 (required argument) – This is an integer specifying the numerator degrees of freedom.
- Deg_freedom2 (required argument) – This is an integer specifying the denominator degrees of freedom.
Example: Let’s look at some Excel F.INV.RT function examples and explore how to use the F.INV.RT function as a worksheet function in Microsoft Excel:
To find out the inverse of the F probability distribution using the F.INV.RT function, we will use the following formula:
- If either deg_freedom1 or deg_freedom2 is a decimal number, it is truncated to integers by MS Excel.
- #NUM! error – Occurs if either:
- The probability that is provided is less than or equal to 0 or greater than 1; or
- The argument deg_freedom1 or deg_freedom2 is less than 1.
- #VALUE! error – Occurs when any of the arguments provided are non-numeric.
- The function was introduced in MS Excel 2010 and is available in subsequent versions.
- INV.RT seeks that value x such that F.DIST.RT(x, deg_freedom1, deg_freedom2) = probability. So, the precision of F.INV.RT depends on the precision of F.DIST.RT. F.INV.RT uses an iterative search technique. If the search fails to converge after 64 iterations, the function returns the #N/A error value.